A. IRVING ON SOME RECENT SECTIONS NEAR NOTTINGHAM. 513 



54. Some Becent Sections near Nottingham. By the Bev. A„ 

 Irving, B.Sc, B.A.., F.G.S, (Head June 21, 187G.) 



[Abridged.] 



The author refers to papers on this district previously published*. 

 In his previous paper on the district, reasons had been given for 

 considering the Permian and the Triassic strata to be much more 

 closely related to one another than is generally stated in the text- 

 books, and for questioning the propriety of attempting to draw any 

 hard and fast line of demarcation between the two formations, at 

 least so far as they are represented in the north-eastern area. For 

 further proof of the reasonableness of the position taken by him 

 then, the author of the present paper refers to the careful and accu- 

 rate paper of Mr, E. "Wilson, F.G.S., of Nottingham, whose wholo 

 life has been passed in the district, and whose observations may bo 

 thoroughly relied upon. The description of the sections described 

 by Mr* Wilson were included in the present paper, but are omitted in 

 this abstract ; and the reader is simply referred to the paper at p. 533 

 of the present Quarterly Journal for an account of a section which 

 must strike every one who examines it as one of the most valuable 

 pieces of evidence yet obtained of the relation that subsists between 

 the Permian and the underlying Coal Measures. 



There is an interesting point, however, in connexion with this 

 particular geological horizon, which has not been touched upon by 

 the author of the paper last referred to, and which illustrates the ex- 

 treme difficulty which must have presented itself to the minds of 

 the Geological-Survey officers in the earlier days of their work, when 

 the extension of railways and coal-mining had not supplied such an 

 ample store of data as we possess at present. Beference is here 

 made to the uppermost strata of the Coal Measures, and particularly 

 to a portion of them consisting of red sandstones and grits, with 

 intcrbedded shales, known locally to mining-engineers as the 

 " Bothcrham Bock." This rock has not been penetrated near Not- 

 tingham, as it lies too high in the series to reach so far south as 

 that place, which is probably not far from the southern limits of 

 the synclinal basin in which the Coal Measures lie; but it was 

 pierced in the Shire-Oak Pit, near "Worksop. It crops out some 

 miles to the west of that place. Prof. Hull, in the 1873 edition of 

 his work on the Coal-Fields of Great Britain, has included the 

 strata in question among the Upper Coal Measures, thus confirming 

 the judgment of local observers ; and on referring to the earliest 

 edition (1852) of the map of the district issued by the Geological 

 Survey, we find it represented there also as a part of the Coal 



* ]. Memoirs of the Geological Survey, by Prof. Hull, F.R.S., and Mr. T. 

 Aveliug, F.G.S. 

 2. " Notes on the Geology of the Nottingham District," by A. Irving, F.G.S., . 

 Proceedings of the Geologists' Association, January, 1874. 



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